How can I tell if I have a CD burner or DVD burner?

If you have a DVD burner you will be able to burn DVDs and CDs. If you have just a CD burner you will only be able to write CDs.

On a Windows computer: generally you can tell what kind of burner you have simply by looking at the drive. If it’s a CD-RW drive, you’ll see the word CD-RW or CD-R or the phrase Compact Disk Re-writable marked on the front of the drive. If it’s a DVD burner, you’ll seeDVD-RW or DVD-R or DVD+RW marked on the drive. If you can’t tell from looking at the drive, right click on My Computer and select properties. Then click on the Hardware tab and click the Device Manager button. You’ll be able to tell what type of drive you have from the list of devices on your system.
On a Mac: go to the Apple menu and select About This Mac. Then click on More Info. This will launch the Apple System Profiler (ASP). Once ASP has finished starting up, look for the Hardware category and then select the Disc Burning sub category. Click on Disc Burning and tell you what type of drive you have.